{"id":33674,"date":"2019-03-04T17:47:01","date_gmt":"2019-03-04T17:47:01","guid":{"rendered":"\/forum\/forums\/topic\/extracting-the-normal-unit-vectors-of-elements-using-command-apdl-and-use-of-the-nlhpre-variable\/"},"modified":"2019-03-04T17:47:01","modified_gmt":"2019-03-04T17:47:01","slug":"extracting-the-normal-unit-vectors-of-elements-using-command-apdl-and-use-of-the-nlhpre-variable","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/extracting-the-normal-unit-vectors-of-elements-using-command-apdl-and-use-of-the-nlhpre-variable\/","title":{"rendered":"Extracting the normal unit vectors of elements using Command (APDL) and use of the NLHPRE variable"},"content":{"rendered":"

Dear All,<\/span><\/p>\n

<\/p>\n

I have 2 questions faced when doing post-processing on a simple case in the ansys mechanical – Transient Structural (workbench) and I appreciate the help from ANSYS community:<\/span>

Assuming a simple hollow cylinder with both ends fixed. I apply a pressure on the external surface and run the model.<\/span>

Question1: I expect the pressure value on the external surface to be equal to the externally applied pressure. I noticed the variable (NLHPRE  – Pressure) exists in the available quantities in workbench. So I used that but the reported pressure value from NLHPRE is not matching with the external pressure. What does the NLHPRE represent and how can I get the pressure value at the external surface (matching with the applied pressure)?<\/span><\/p>\n

<\/p>\n


Question2: I would like to use the Commands (APDL) to get the normal vectors to the elements on the surfaces and calculate the traction. What would be the right commands to use and how can I implement that? <\/span>

Thank you<\/span>

Regards<\/span><\/p>\n

<\/p>\n

Masoud<\/span><\/p>\n","protected":false},"template":"","class_list":["post-33674","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t